Day 8
181 words, 写作时间23分钟。
The reading passage provides three possible reasons for the extinction of Steller’s sea cow, i.e., local people eating up all the sea cow they could hunt for food, environment-inflicted food shortage for this sea animal, and European fur traders’slaughter. However, these three theories are all challenged by the points raised in the listening material on good standing.
First, the small population of Siberians couldn’t have consumed that much food, let alone the sea cow are actually massive animals, meaning a baby sea cow could have fed a village for month-long. Therefore, the local people weren’t the main reason to cause the animal’s extinction.
Second, the sea cow couldn’t have faced any food shortage, for it’s major food source, kelp, didn’t suffer a drop in numbers on account of ecosystem disturbances, any more than any other marine animals (say, whale) did.
Third, the wrongly accused European fur traders, the alleged culprit, came to the Bering Island long after the sea cow herd had already been hit by a sharp population decrease, therefore highly unlikely to inflict any disaster to this marine mammal.
